London: With huge reflecting pools, waterfalls and an underground museum, the 9/11 memorial at the World Trade Center site, being built at an estimated $700 million, will cost a whopping $60 million a year to operate, a media report said.
The National September 11 Memorial and Museum drew around 4.5 million visitors in its first year, the Daily Mail reported.
Officials at the 9/11 memorial said they were facing challenges over comparisons to other national memorials.
The National Park Service spent $8.4 million this year to operate and maintain the Gettysburg National Military Park and $3.6 million for the monument that includes the USS Arizona Memorial at Pearl Harbor.
The Arlington National Cemetery, which has more than 14,000 graves and receives four million visitors a year, costs $45 million annually.
The 9/11 memorial officials plan to spend at least $12 million per year on private security because of terrorism fears.
"The fact of the matter is that this was a place that was attacked twice," Joseph Daniels, the foundation's president and chief executive, was quoted as saying by the Daily Mail.
Operating two massive fountains that mark the spots where the twin towers once stood will cost $4.5-$5 million annually, according to a spokesman.
The museum was supposed to open this month, but construction almost ceased a year ago because of a funding squabble between the foundation and the Port Authority of New York and New Jersey, which owns the land the memorial sits on.
Daniels said it will take at least a year for the museum to open once construction resumes. The site may not be fully complete until at least 2014, he said.
Visitors will be allowed into the above-ground portions of the memorial for free, but will have to pay to descend into the museum's exhibition space.
The museum will have portraits of the nearly 3,000 victims, oral histories of the tragedy and artefacts such as the staircase World Trade Center workers used to flee on 9/11.